Introduction to Sandhyavandhanam

Sandhyavandana is a mandatory religious ritual that needs to be performed by all twice-born people of Hinduism. Especially brahmins who are initiated into the sacred thread ceremony called as Upanayanam, and instructed in its execution by a Guru (a qualified spiritual teacher). Sandhyavandanam consists of excerpts from the Vedas that are to be performed thrice daily at morning (prātaḥsaṃdhyā), at noon (mādhyānika), and in the evening (sāyaṃsaṃdhyā).
Sandhyavandanam is the oldest extant liturgy in world religion. It may be a practice descended from the much older daily Agnihotra.

Sandhyavandanam literally means salutation to Sandhya. Sandhya literally means transition moments of the day namely the two twilight: dawn and dusk and the solar noon. Thus Sandhyavandanam means salutation to twilight or solar noon.

The term sandhyā is also used by itself in the sense of "daily practice" to refer to the performance of these devotions at the opening and closing of the day. [1][2]
[3][4] The steps in the Sandhyavandan always include the following essential ones:
1. Achamana consists of Nama Sankirthana---taking the names of the Lord
2. Pranayama is the ritual purification of internals via breathing exercises
3. Marjana is a ritual self-purification
4. Mantra Prokshanam is a prayer for atonement of sins
5. Aghamarshana (performed by some schools, especially Rig Vedins) is a prayer for forgiveness of sins
6. Gayathri japa is meditation
7. Upasthanam is prayer to Mitra (in the morning prayer) & Varuna (in the evening prayer)
8. AbhivAdana is a salutory introduction offered to all deities. It usually follows a prostration to the deities of each direction ("dikpaalas")